US-12624184-B2 - Method, process and system for recycling an asphalt-based roofing material

Abstract

The present disclosure provides a method, process and system for recycling an asphalt-based roofing material. In particular, the method, process and system are capable of removing and recovering an aggregate product, fiber product and an asphalt product from the asphalt-based roofing material. The aggregate, fiber and asphalt products each may be reused in a variety of applications.

Inventors

• Terry Alan Charles
• Gord Johnson
• Barry Diebold

Assignees

• NORTHSTAR CLEAN TECHNOLOGIES INC.

Dates

Publication Date

20260512

Application Date

20240405

Claims (17)

1. 1 . A method for removing aggregate from an asphalt-based roofing material comprising: removing aggregate that has been mechanically separated from an asphalt-based roofing material, wherein the aggregate has been mechanically separated from the asphalt-based roofing material with at least one pressurized stream of fluid.
2. 2 . The method of claim 1 , wherein the asphalt-based roofing material has been contacted with the at least one pressurized stream of fluid within a separation tank or vessel.
3. 3 . The method of claim 1 , wherein the asphalt-based roofing material has been contacted with at least two pressurized streams of fluid.
4. 4 . The method of claim 3 , wherein the at least two pressurized streams of fluid are opposed to one another.
5. 5 . The method of claim 1 , wherein the at least one pressurized stream of fluid is directed towards an impact surface.
6. 6 . The method of claim 1 , wherein the fluid comprises water.
7. 7 . The method of claim 6 , wherein the fluid is at ambient temperature.
8. 8 . The method of claim 1 , wherein the asphalt-based roofing material is pretreated to crush or grind the asphalt-based roofing material.
9. 9 . The method of claim 1 , further comprising the step of recovering the separated aggregate.
10. 10 . The method of claim 9 , wherein at least about 90 wt. % of a total weight of aggregate originally present in the asphalt-based roofing material is recovered as separated aggregate.
11. 11 . The method of claim 9 , wherein the recovered aggregate is dewatered or dried to remove fluid from the aggregate.
12. 12 . The method of claim 1 , wherein the asphalt-based roofing material comprises roofing shingles.
13. 13 . The method of claim 1 , further comprising the step of recovering an asphalt-fiber slurry.
14. 14 . The method of claim 13 , wherein the asphalt-fiber slurry is dewatered or dried in a drying apparatus to remove fluid from the asphalt-fiber slurry and produce an aggregate-free asphalt-based roofing material.
15. 15 . The method of claim 14 , wherein the drying apparatus is a vacuum dryer, tray dryer, fluidized bed dryer, rotary dryer, dewatering screen, spray dryer, centrifuge or a hydrocyclone.
16. 16 . The method of claim 14 , wherein at least 70 wt. % of a total weight of fluid originally present in the asphalt-fiber slurry is removed.
17. 17 . The method of claim 14 , wherein the fluid removed from the asphalt-fiber slurry is recycled in the at least one pressurized stream of fluid.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser. No. 17/964,571 filed on Oct. 12, 2022, which is a Divisional of U.S. patent application Ser. No. 17/681,407 filed on Feb. 25, 2022 (now U.S. Pat. No. 11,492,455 issued on Nov. 8, 2022). The entire contents of each of the aforementioned applications are incorporated in their entirety by reference herein. TECHNICAL FIELD The present disclosure generally relates to methods, processes and systems for the recycling of asphalt-based roofing materials. In particular, the present disclosure generally relates to methods, processes and systems to separate the constituents of an asphalt-based roofing shingle and recover and reuse such constituents in various applications. BACKGROUND A significant amount of unwanted material is generated from the manufacture, installation and removal of asphalt-based materials, such as roofing shingles. For example, an average residential roof removal generates 1-3 tons of roofing shingles, depending on whether the old roof consisted of 1 or 2 layers. All this adds up to an estimated total of approximately 13.5 million tons of torn-off shingles every year nationwide in North America, plus an additional 1 million tons of scrap generated by the shingle manufacturing process. This is a huge amount of unwanted material destined for already overcapacity landfills, especially since torn-off roofing shingles take at least 300 years to break down and as such some jurisdictions are increasing disposal fees, limiting disposal limits to very low percentages or banning completely. Moreover, roofing shingles cannot be composted and burning or incineration is not recommended, as it may result in the emissions of gases hazardous to human health. Since the materials in roofing shingles are similar to those materials used in hot mix asphalt cement and other road applications, unwanted roofing shingles have been identified as a material that may be diverted from landfill disposal and recycled and reused, however use in road applications is limited to very low percentages in some jurisdictions or completely banned in others. A roofing shingle is typically made up of different materials, including cellulose (paper) or a fiberglass mat, an asphalt coating and a layer of aggregate granules dispersed on the coating. Developing technically viable and cost-effective recycling processes has proven to be challenging since these materials are difficult to break down/separate and therefore typically require complex process steps or equipment. For example, the asphalt and aggregate strongly adheres to one another making their separation difficult. A further problem associated with efforts to recycle these materials concerns the difficulty in shredding the shingles on a bulk basis. Because of their high granular material content, roofing shingles act like large pieces of sandpaper and as such, large piles of roofing shingles are extremely difficult to drag, flow, separate, or handle. Additionally, recycling of roofing shingles normally requires modification to standard grinding, screening, separation and dust control equipment in order to reach the desired end use products. Some past recycling processes have used milling machines, such as rolling mills, bag mills, hammer mills, saw mills, etc. to produce a recycled roofing material which can only be used in road construction or as other similar “filler” material. Other processes have used a solvent to break down the roofing shingle, for example, U.S. Pat. No. 8,789,773 discloses a process, in which a solvent is first added to an asphalt-based material to form a mixture containing asphalt dissolved in solvent and a solids material. The solids material can be separated out by centrifugation or filtration while the asphalt dissolved in solvent can be fractionally distilled to separate the heavier asphalt phase from the lighter solvent phase. In WO 2020/041347, a process is disclosed that includes contacting a roofing shingle with a petroleum chemical in a screened tubular rotating apparatus to separate asphalt from the sand and fiberglass. U.S. Pat. App. Publ. No. 2019/0256783 also discloses a process whereby roofing shingles are placed in a dissolution vessel and a solvent stream is added to the vessel to dissolve the asphalt under agitation to yield a solids rich stream and a solvent and bitumen rich stream which can be passed through a flash drum to yield a solvent rich stream and a bitumen rich stream. Finally, U.S. Pat. No. 4,222,851 discloses a process in which roofing shingles are repeatedly washed with solvent and the solvent and asphalt are subsequently separated from one another in first and second stage evaporators. Nevertheless, there is a continuing need to provide improved methods and processes in which torn-off roofing shingles and shingle material which is the by-product of the manufacture of new roofing shingles can be recycled and reused, thus av